Revenue from Contracts with Customers - Disaggregation of Revenues (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Total revenue	$ 13,000	$ 11,945	$ 12,148
Servicing fees
Disaggregation of Revenue [Line Items]
Total revenue	5,016	4,922	5,087
Management fees
Disaggregation of Revenue [Line Items]
Total revenue	2,124	1,876	1,939
Foreign exchange trading services
Disaggregation of Revenue [Line Items]
Total revenue	1,401	1,265	1,376
Securities finance
Disaggregation of Revenue [Line Items]
Total revenue	438	426	416
Software and processing fees
Disaggregation of Revenue [Line Items]
Total revenue	888	811	789
Other fee revenue
Disaggregation of Revenue [Line Items]
Total revenue	289	180	(1)
Total fee revenue
Disaggregation of Revenue [Line Items]
Total revenue	10,156	9,480	9,606
Net interest income
Disaggregation of Revenue [Line Items]
Total revenue	2,923	2,759	2,544
Total other income
Disaggregation of Revenue [Line Items]
Total revenue	(79)	(294)	(2)
Operating Segments | Investment Servicing
Disaggregation of Revenue [Line Items]
Topic 606 revenue	6,272	6,118	6,282
All other revenue	4,384	4,042	3,857
Total revenue	10,656	10,160	10,139
Operating Segments | Investment Servicing | Servicing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	5,016	4,922	5,087
All other revenue	0	0	0
Total revenue	5,016	4,922	5,087
Operating Segments | Investment Servicing | Management fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	0	0	0
Total revenue	0	0	0
Operating Segments | Investment Servicing | Foreign exchange trading services
Disaggregation of Revenue [Line Items]
Topic 606 revenue	386	344	363
All other revenue	862	796	908
Total revenue	1,248	1,140	1,271
Operating Segments | Investment Servicing | Securities finance
Disaggregation of Revenue [Line Items]
Topic 606 revenue	185	225	233
All other revenue	230	177	164
Total revenue	415	402	397
Operating Segments | Investment Servicing | Software and processing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	685	627	599
All other revenue	203	184	190
Total revenue	888	811	789
Operating Segments | Investment Servicing | Other fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	188	145	46
Total revenue	188	145	46
Operating Segments | Investment Servicing | Total fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	6,272	6,118	6,282
All other revenue	1,483	1,302	1,308
Total revenue	7,755	7,420	7,590
Operating Segments | Investment Servicing | Net interest income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	2,899	2,740	2,551
Total revenue	2,899	2,740	2,551
Operating Segments | Investment Servicing | Total other income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	2	0	(2)
Total revenue	2	0	(2)
Operating Segments | Investment Management
Disaggregation of Revenue [Line Items]
Topic 606 revenue	2,262	2,001	2,021
All other revenue	82	78	(35)
Total revenue	2,344	2,079	1,986
Operating Segments | Investment Management | Servicing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	0	0	0
Total revenue	0	0	0
Operating Segments | Investment Management | Management fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	2,124	1,876	1,939
All other revenue	0	0	0
Total revenue	2,124	1,876	1,939
Operating Segments | Investment Management | Foreign exchange trading services
Disaggregation of Revenue [Line Items]
Topic 606 revenue	138	125	82
All other revenue	0	0	0
Total revenue	138	125	82
Operating Segments | Investment Management | Securities finance
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	23	24	19
Total revenue	23	24	19
Operating Segments | Investment Management | Software and processing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	0	0	0
Total revenue	0	0	0
Operating Segments | Investment Management | Other fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	35	35	(47)
Total revenue	35	35	(47)
Operating Segments | Investment Management | Total fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	2,262	2,001	2,021
All other revenue	58	59	(28)
Total revenue	2,320	2,060	1,993
Operating Segments | Investment Management | Net interest income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	24	19	(7)
Total revenue	24	19	(7)
Operating Segments | Investment Management | Total other income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	0	0	0
Total revenue	0	0	0
Other
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	0	(294)	23
Total revenue	0	(294)	23
Other | Servicing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	0	0	0
Total revenue	0	0	0
Other | Management fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	0	0	0
Total revenue	0	0	0
Other | Foreign exchange trading services
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	15	0	23
Total revenue	15	0	23
Other | Securities finance
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	0	0	0
Total revenue	0	0	0
Other | Software and processing fees
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	0	0	0
Total revenue	0	0	0
Other | Other fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	66	0	0
Total revenue	66	0	0
Other | Total fee revenue
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	81	0	23
Total revenue	81	0	23
Other | Net interest income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	0	0	0
Total revenue	0	0	0
Other | Total other income
Disaggregation of Revenue [Line Items]
Topic 606 revenue	0	0	0
All other revenue	(81)	(294)	0
Total revenue	$ (81)	$ (294)	$ 0